Pump priming apparatus



April 29, 1941. c. F. SMITH 2,240,057

PUMP PRIMING APPARATUS Filed March 29, 1937 3 Sheets-Sheet 1 INVE TOR W jm ATTOR EY5 April 29, 1941. c. F. SMITH 2,240,057

PUMP PRIMING APPARATUS Filed March 29, 1937 3 Sheets-Sheet 2 T0 PUMP- 5; 1a I M 22 is: 7 \AW 2/ H I rain 6 m [/1 ii J i 15 lfuufliili" I M 1 F?! w! E?! I I .L ZJ I w I a k [1 April 29, 1941. c. F. SMITH PUMP PRIMING APPARATUS 3 Sheets-Sheet 3 /IIIII IN V EN TOR.

Filed March 29, 1937 AT; ERNEYS.

Patented Apr. 29, 1941 PUMP PRIMING' APPARATUS Carlisle F. Smith, Elmira, N. Y., assignor to American-La France-Foamite Corporation, Elmira, N. Y., a corporation of New York Application March 29, 1937, Serial No. 133,679

3 Claims.

The invention relates to primers for rotary or centrifugal pumps, such as are used on motorized fire apparatus and driven by the internal combustlon engine that also propels the vehicle,

although the invention may be usefully employed also in other relations, the purpose being to- 7 in such line an automatic shut-ofi operating to exclude the possibility of water being drawn into the suction producing mechanism, whether that be the engine proper or a device driven by it. The shut-off is positively operated by the 7 weight or impact of the water encountering it, as distinguished from float devices, heretofore proposed for this purpose. The invention further consists in supplemental details and combinations thereof, as herein described and pointed out in the claims, and certain of which may have utility independently of the particular shut-off mechanism used.

In the accompanying drawings,

Fig. 1 is a diagrammatic view of the illustrating its mode of operation;

Fig. 2 an axial section through the automatic shut-off valve;

Fig. 3 a detail of the engine connection; and

Figs. 4, 5, 6 and 7 respectively elevation and sections of the discharge gate.

In Fig. 1, the centrifugal pump to be primed is shown conventionally at 9, its suction pipe at 2 and its discharge conduit at 3, these being 01 the twin type and each provided with a discharge valve indicated at 4, specially organlzed for use in suction priming systems, as later described.

It will be understood that the pump intake 2 is intended to be extended into the source of water supply at a lower level, a pond or river for example, and that the purpose is to pump such water through the discharge conduits and valves 4 to the fire, .or other place of use. It will be understood further that the pump is driven by the internal combustion engine indicated in outline at 5.

The pump is primed by sucking the water up into the pump casing, for which purpose a connection is made to the top of the pump, through which engine-produced suction is transmitted to system its interior, the discharge gates of course being closed. As illustrated herein, the suction is derived from the intake manifold of the engine and may be so derived while such manifold continues its normal fuel supply function, or when the carburetor has been entirely shut off and the cylinders normally served thereby are driven by other power cylinders, as later explained. In Fig. 1 the suction is indicated as derived from the carburetor without stopping its normal action, proper safeguards being provided against impairing the carburetion.

The suction priming line is marked 6 and includes a primer control valve 7!, subject to operation by the operator, a check valve 8 closing toward-the pump, an accumulator space 9, and the automatic shut-off Ill, connected as above stated to the engine carburetor ll. This line is also provided with one or more check valve outlets l2, each provided with inwardly closing check valves, the purposes of these outlets being to permit the escape of water when required, but prevent ingress of air during the suction priming, and one of them serves as an indicator, as presently explained.

The automatic shut-ofi device comprises the main casing is, which can be attached to any convenient part of the vehicle, usually under the hood, and contains a water-operated device or catcher l3, movably mounted in the casing and normally held elevated by a spring M. The gravity or impact of water entering this catcher from the pim line 6 through the holes id is adapted to depress it, over-balancing the spring,

which action is arranged to close the suction line against the further passage of water into the catcher. To accomplish this purpose, the catcher is susceptible of various design and as shown herein is merely a cylindrical receptacle mounted to slide up and down on a boss l6 forming part of the casing cover and on a tube ll appropriately fixed in the bottom of the casing. The shut-off valve proper, marked it, closes in the direction of flow through the suction line and is carried on a hollow stem l9, which slides on the fixed tube H and is provided with one or more ports Zll, adapted to register with the ports H in the fixed tube l1, when the receptacle is overbalanced by the water. In such position, the shut-01f valve It! being closed, any water in the receptacle may drain out through the tube I 7 to the ground, leaving the pressure on top of the poppet-type valve to continue its closed condition, and hold the spring compressed, so long as such pressure persists. The space within the receptacle I3 is in communication with the en-' gine suction through the holes 22 at its upper end and the space in the casing surrounding the receptacle, which as indicated is tapped for connection to the pipe line that runs to the engine.

When the pump is to be primed, the engine being in action, and the pump intake having been lowered into the source of water, the operator closes the discharge gates 4, so as to seal the interior of the pump against ingress of atmosphere, and then opens the primer control valve l as by pulling on the handle 24 (Fig. 1). This connects the engine to the pump through the suction line 6, the pump being in action but empty of water. The suction transmitted to the pump draws the water up into it and thence into the suction line 6. When the casing is full the pressure created by the pump impeller forces water into the suction line toward the engine and more or less of it will flow out through the check valve outlets. One of thelatter may be provided with a jet pipe, or the like, located close to the operators station so as to serve as a visual and audible signal to him indicating that the pump has been primed. Such a jet pipe is indicated at 25 in the diagram. The operator then closes the primer control valve 1 and opens one of the discharge gates 4, and pumping begins.

It will be appreciated that before this has happened a considerable portion of water may have passed through the suction line toward the engine. Enough may have passed to fill the accumulator space 9 and in that case water will flow past the normally open poppet valve l8 into the water balance l3, which will be instantly depressed, either by the weight of the water or by its impact aided by the suction, thereby instantly closing the suction line against any possibility of the water passing further. Such water as arrives in the over-balanced receptacle promptly drains out through the hollow tube l1, above referred to. The handle 26, indicated as attached to the cross pin, which unites the valve stem l9 to the balanced receptacle, is for the purpose of manually operating the valve or feeling of it, as security against the possibility of its sticking.

It is preferable, although not always necessary, depending on the type of carburetor used, to couple the operating handle 24 of the control valve '3 with the normal carburetor choke, so that the latter will be closed when the suction line is open. And also, depending on the type of carburetor, it may sometimes be desirable otherwise to guard against disturbing the normal carburetion. Various means are known for this purpose and need not be here described further than to say that in the case illustrated the carburetor choke is closed by a Bowden wire 21, connected to the handle 24, so that pulling on the handle opens the suction line and closes the choke. The float bowl of the carburetor is shown balanced to the interior of the carburetor by an equalizing tube H.

When the system is used on a V-type two-carburetor engine, the whole of one side of the engine can be and preferably is used as the suction source. This hook-up is indicated in Fig. 3, where the two manifolds are marked 28 and their carburetors 29 and the suction line 6 is connected to only one of them. The engine is omitted from this figure for clearness. The throttle of one of the carburetors is made to close tight and connected to the Bowden wire, as indicated, so that when the control handle 24 has been pulled the suction will be produced by the action of the cylinders on one side of the engine driven by the cylinders on the other side, running normally on their own carburetor.

It is pointed out that the accumulator space 9 is merely precautionary to guard the system against the possibility that an advance slug of water in the pipe, reaching the balance device, might close the shut-oii' valve prematurely, but other means can be provided for this purpose when such precaution is considered necessary. With some dispositions of the suction line it is not necessary. The check valve 8 is for holding the vacuum in the pump, if, for any reason, the source of suction should fail during the priming operation.

It is obviously important that the discharge gate i shall close tightly against air leakage during the suction period when atmospheric pressure is acting upon it, reversely to the action on it of the water when the pump is in operation, and it is likewise desirable that the gate shall operate easily when subject to the Water pressure of the pump. To accomplish tight seating and easy turning in discharge gates for suction primed pumps and, according to this invention, the gate is provided with a main shoe 30 for water and an auxiliary shoe 3| for air. (See Figs. 4 to 7.) The two shoes are loosely connected to each other by a rabbet-slot connection and pressed apart and against the interior surface of the valve casing by a bow spring 32. It may be said that they are thus telescopically related, with the spring tending to distend them. In the present case, the rabbet slot, marked 33, is formed in the auxiliary shoe 3| and the spring is in the slot. The valve spindle 34 has a cranked part 35 loosely fitting in a slot in the main shoe by which the latter is successively lifted from its seat and rotated when the spindle is turned. The action is as follows: When the valve is subject to priming suction inward leakage of air is prevented by the floating shoe 3!, which is thus pressed to its seat by atmosphere leaking past the main shoe, as well as by the spring. When the valve is subject to water pressure, leakage of the water is prevented by the main shoe 30, which is pressed to its seat mainly by the water escaping past the other shoe, and to some extent also by the spring. When the valve is to be opened under water pressure the spindle crank is turned within the confines of its slot in the main shoe, so that its hard steel shoulder 36 bears by its corner against a corresponding hard steel wear piece 31, fastened to the inside of the main shoe, and lifts or pries the main shoe from its seat, at the same time somewhat compressing the bow spring. This lifting is done by the benefit of favorable leverage, as will be apparent, and acts to crack the main valve from its seat and thereby relieve its friction on the' valve casing, so that it then can be turned easily by continued rotation of the spindle. Thus the discharge gate is easy turning, nothwithstanding that it is leak proof in opposite directions to air and water respectively.

I claim:

1. in combination, a pipe line, a chamber connected in said pipe line normally closed to atmosphere and subject to partial vacuum created in the pipe line on one side of said chamber, a poppet form valve controlling the flow through the part of said pipe line leading into said chamber and adapted to be helped in its closing action by the efiect of said partial vacuum, a valve-opcrating receptacle movably mounted inside of said chamber and subject to the impact 01' air and water flowing from said pipe line into said chamber in the direction to close said valve, said receptacle having such resistance to movement as to be unmoved by air flow alone and when subject to the impact and weight of said water being adapted in conjunction with said vacuum to produce a quick and full-throw closing movement of said valve, and manually operated means controlling a passage independent of said pipe line from the receptacle to the exterior of said chamher.

2. In combination, a pipe line, a chamber connected in said pipe line normally closed to atmosphere and subject to partial vacuum created in the pipe line on one side of said chamber,

' a manual valve and a popp t form valve controlling the flow through the part of said pipe line leading into said chamber, an indicator connected in said pipe line between said poppet form valve and said manual valve, said poppet form valve being adapted to be helped in its closing action by the effect of said partial vacuum, a valve-operating element movably mounted inside or said chamber and subject to the impact of air and water flowing from said pipe line into said chamber in the direction to close said poppet form valve, said element having such resistance to movement as to be unmoved by air flow alone and when subject to the impact and-weight of said water being adapted in conjunction with said vacuum to produce a quick and full-throw closing movement of said valve poppet form.

3. In combination, a pipe line, a chamber connected in said pipe line normally closed to atmosphere and subject to partial vacuum created in the pipe line on one side of said chamber, a poppet form valve controlling the flow through the part of said pipe line leading into said chamber, and provided with a hollow drainage stem adapted to form a communication to the exterior of said chamber, said valve being adapted to be helped in its closing action by the efle'ct of said partial vacuum, a valve-operating element movably mounted inside of said chamber and subject to the impact or air and water flowing in said pipe line into said chamber in the direction to close said valve, said element having such resistance to movement as 'to be unmoved by air flow alone and when subject to the impact and weight of said water being adapted in conjunction with said vacuum to produce a quick and full-throw closing movement 01' said valve.

cARmsLE F. SMITH. 

